Non-Human Primates Harbor Diverse Mammalian and Avian Astroviruses Including Those Associated with Human Infections

Seven zoonoses — human infections of animal origin — have emerged from the Coronaviridae family in the past century, including three viruses responsible for significant human mortality (SARS-CoV, MERS-CoV, and SARS-CoV-2) in the past twenty years alone. These three viruses, in addition to two older CoV zoonoses (HCoV-229E and HCoV-NL63) are believed to be originally derived from wild bat reservoir species. We review the molecular biology of the bat-derived Alpha- and Betacoronavirus genera, highlighting features that contribute to their potential for cross-species emergence, including the use of well-conserved mammalian host cell machinery for cell entry and a unique capacity for adaptation to novel host environments after host switching. The adaptive capacity of coronaviruses largely results from their large genomes, which reduce the risk of deleterious mutational errors and facilitate range-expanding recombination events by offering heightened redundancy in essential genetic material. Large CoV genomes are made possible by the unique proofreading capacity encoded for their RNA-dependent polymerase. We find that bat-borne SARS-related coronaviruses in the subgenus Sarbecovirus, the source clade for SARS-CoV and SARS-CoV-2, present a particularly poignant pandemic threat, due to the extraordinary viral genetic diversity represented among several sympatric species of their horseshoe bat hosts. To date, Sarbecovirus surveillance has been almost entirely restricted to China. More vigorous field research efforts tracking the circulation of Sarbecoviruses specifically and Betacoronaviruses more generally is needed across a broader global range if we are to avoid future repeats of the COVID-19 pandemic.

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Thymol Chemistry: A Medicinal Toolbox

Current Bioactive Compounds ◽

10.2174/1573407214666180503120222 ◽

2019 ◽

Vol 15 (5) ◽

pp. 454-474 ◽

Cited By ~ 4

Author(s):

Jyoti ◽

Divya Dheer ◽

Davinder Singh ◽

Gulshan Kumar ◽

Manvika Karnatak ◽

...

Keyword(s):

Web Of Science ◽

Biological Activities ◽

Controlled Clinical Trials ◽

Food Preservative ◽

Beneficial Effects ◽

Therapeutic Benefits ◽

Trachyspermum Ammi ◽

Randomised Controlled ◽

Human Infections ◽

Potential Use

Background: Thymol is a natural phenolic monoterpenoid widely used in pharmaceutical and food preservative applications. Thymol isomeric with carvacrol, extracted primarily from Thymus species (Trachyspermum ammi) and other plants sources such as Baccharisgrise bachii and Centipeda minima, has ethnopharmacological characteristics. Methods: This review was prepared by analyzing articles published on thymol moiety in last decade and selected from Science Direct, Scopus, Pub Med, Web of Science and SciFinder. The selected articles are classified and gives brief introduction about thymol and its isolation, illustrates its natural as well as synthetic sources, and also therapeutic benefits of thymol worldwide Results: Thymol has been covering different endeavors such as antimicrobial, antioxidant, antiinflammatory, antibacterial, antifungal, antidiarrhoeal, anthelmintic, analgesic, digestive, abortifacient, antihypertensive, spermicidal, depigmenting, antileishmanial, anticholinesterase, insecticidal and many others. This phenolic compound is among the essential scaffolds for medicinal chemists to synthesize more bio-active molecules by further derivatization of the thymol moiety. Conclusion: Thymol is an interesting scaffold due to its different activities and derivatization of thymol is proved to enhance its biological activities. However, more robust, randomised, controlled clinical trials would be desirable with well-characterised thymol preparations to corroborate its beneficial effects in diseased patients. Moreover, in view of the potential use of thymol and thymol-rich essential oils in the treatment of human infections, comprehensive studies on chronic and acute toxicity and also teratogenicity are to be recommended.

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Fournier’s gangrene due to Salmonella Typhimurium in a healthy male: a rare aberrant infection

Infectious Disorders - Drug Targets ◽

10.2174/1871526520666201117143421 ◽

2020 ◽

Vol 20 ◽

Author(s):

Varsha Gupta ◽

Lipika Singhal ◽

Kritika Pal ◽

Mani Bhushan ◽

Rajeev Sharma ◽

...

Keyword(s):

Salmonella Typhimurium ◽

Systemic Disease ◽

External Genitalia ◽

Fournier’S Gangrene ◽

The Body ◽

Healthy Male ◽

Fournier's Gangrene ◽

Salmonella Infections ◽

Chief Complaints ◽

Human Infections

Introduction: Human Salmonella infections have been classically distinguised into diseases caused by typhoidal and non-typhoidal salmonella (NTS). Typhiodal salmonella includes S. enterica serovars Typhi and Paratyphi that cause the systemic disease but are restricted to human infections, while NTS consists mainly of other serovars that predominantly cause self-limiting gastroenteritis in humans. Localisation of foci with persisting infection occurs due to dissemination of the bacteria throughout the body and can cause a variety of rare clinical syndromes at aberrant sites. Fournier’s gangrene, a rapidly progressive, often fatal, necrotizing fasciitis of the external genitalia and perineum due to Salmonella Typhimurium, is a rare manifestation and has never been reported. Case: A 22-year-old male, apparently healthy patient with no relevant past medical history presented to surgical emergency with chief complaints of swelling of bilateral scrotal area. Infective etiology was considered and a diagnosis of fournier’s gangrene was made. Pure growth of Salmonella Typhimurium was obtained after repeated subculture and was identified biochemically and on serotyping, as Salmonella enterica serotype Typhimurium using specific antisera. Conclusion: In our case report, we describe a case of fournier’s gangrene due to Salmonella Typhimurium in an otherwise healthy male to highlight the unusual presentation of Non typhoidal salmonellae at an aberrant site. We also emphasize the importance of using selective media like Selenite F broth for isolation of Salmonella Typhimurium from a pus sample.

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Mycobacterial biofilms as players in human infections: a review

Biofouling ◽

10.1080/08927014.2021.1925886 ◽

2021 ◽

pp. 1-23

Author(s):

Esmeralda Ivonne Niño-Padilla ◽

Carlos Velazquez ◽

Adriana Garibay-Escobar

Keyword(s):

Human Infections

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A Bacterially-Expressed Recombinant Envelope Protein from Usutu Virus Induces Neutralizing Antibodies in Rabbits

Vaccines ◽

10.3390/vaccines9020157 ◽

2021 ◽

Vol 9 (2) ◽

pp. 157

Author(s):

Kinga Böszörményi ◽

Janet Hirsch ◽

Gwendoline Kiemenyi Kayere ◽

Zahra Fagrouch ◽

Nicole Heijmans ◽

...

Keyword(s):

Envelope Protein ◽

Neutralizing Antibodies ◽

Size Exclusion ◽

Vitro Assay ◽

Usutu Virus ◽

Transmission Electron ◽

Exclusion Chromatography ◽

Efficacious Vaccine ◽

Human Infections

Background: Recently, an emerging flavivirus, Usutu virus (USUV), has caused an epidemic among birds in Europe, resulting in a massive die-off in Eurasian blackbirds. Currently found only in Europe and Africa, it can be envisioned that Usutu virus will follow the path of other flaviviruses, like West Nile virus and Zika virus, and will spread via its mosquito vectors and bird hosts to other parts of the world. Several cases of human infections by Usutu virus have already been published. Anticipating this spread, development of an efficacious vaccine would be highly desirable. Method: This study describes the production in E. coli, purification, and refolding of a partial USUV envelope protein. Prior to immunization, the protein was characterized using size exclusion chromatography, transmission electron microscopy and dynamic light scattering, showing the limited presence of virus-like structures, indicating that the protein solution is probably a mixture of mono and multimeric envelope proteins. Results: Immunizations of two rabbits with the refolded E-protein fraction, mixed with a strong adjuvant, resulted in the generation of neutralizing antibodies, as evidenced in an in vitro assay. Discussion: The way forward towards a subunit vaccine against Usutu virus infection is discussed.

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The Interplay between Campylobacter and the Caecal Microbial Community of Commercial Broiler Chickens over Time

Microorganisms ◽

10.3390/microorganisms9020221 ◽

2021 ◽

Vol 9 (2) ◽

pp. 221

Author(s):

Ilaria Patuzzi ◽

Massimiliano Orsini ◽

Veronica Cibin ◽

Sara Petrin ◽

Eleonora Mastrorilli ◽

...

Keyword(s):

Campylobacter Jejuni ◽

Broiler Chickens ◽

Control Strategies ◽

Chicken Meat ◽

Control Measures ◽

Microbial Network ◽

Gut Colonization ◽

Commercial Broiler ◽

Zoonotic Bacteria ◽

Human Infections

Campylobacter is the most frequent foodborne zoonotic bacteria worldwide, with chicken meat being overwhelmingly the most important reservoir for human infections. Control measures implemented at the farm level (i.e., biosecurity or vaccination), which have been successfully applied to limit other pathogens, such as Salmonella, have not been effective in reducing Campylobacter occurrence. Thus, new approaches are needed to fully understand the ecological interactions of Campylobacter with host animals to effectively comprehend its epidemiology. The objective of this study was to analyse longitudinally the gut microbiota composition of Campylobacter-infected and non-infected farms to identify any difference that could potentially be indicative of gut colonization by Campylobacter spp. Differences in the colonization rate and timing were observed at the farms that became positive for Campylobacter jejuni over the investigated time points, even though in positive tests, the occurrence of Campylobacter jejuni gut colonization was not observed before the second week of the life of the birds. Significant differences were observed in the abundances of specific bacterial taxa between the microbiota of individuals belonging to farms that became Campylobacter positive during the study and those who remained negative with particular reference to Bacteroidales and Clostridiales, respectively. Moreover, Campylobacter colonization dramatically influenced the microbiota richness, although to a different extent depending on the infection timing. Finally, a key role of Faecalibacterium and Lactobacillus genera on the Campylobacter microbial network was observed. Understanding the ecology of the Campylobacter interaction with host microbiota during infection could support novel approaches for broiler microbial barrier restoration. Therefore, evidence obtained through this study can be used to identify options to reduce the incidence of infection at a primary production level based on the targeted influence of the intestinal microbiota, thus helping develop new control strategies in order to mitigate the risk of human exposure to Campylobacter by chicken meat consumption.

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The Immune Correlates of Orthohantavirus Vaccine

Vaccines ◽

10.3390/vaccines9050518 ◽

2021 ◽

Vol 9 (5) ◽

pp. 518

Author(s):

Joon-Yong Bae ◽

Jin Il Kim ◽

Mee Sook Park ◽

Gee Eun Lee ◽

Heedo Park ◽

...

Keyword(s):

Vaccine Development ◽

Zoonotic Transmission ◽

Effective Vaccine ◽

Pandemic Preparedness ◽

Relative Paucity ◽

Immune Correlates ◽

Current Vaccine ◽

Pros And Cons ◽

Human Infections ◽

Sense Of Urgency

Zoonotic transmission of orthohantaviruses from rodent reservoirs to humans has been the cause of severe fatalities. Human infections are reported worldwide, but vaccines have been approved only in China and Korea. Orthohantavirus vaccine development has been pursued with no sense of urgency due to the relative paucity of cases in countries outside China and Korea. However, the orthohantaviruses continuously evolve in hosts and thus the current vaccine may not work as well against some variants. Therefore, a more effective vaccine should be prepared against the orthohantaviruses. In this review, we discuss the issues caused by the orthohantavirus vaccine. Given the pros and cons of the orthohantavirus vaccine, we suggest strategies for the development of better vaccines in terms of pandemic preparedness.

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Organoids to Dissect Gastrointestinal Virus–Host Interactions: What Have We Learned?

Viruses ◽

10.3390/v13060999 ◽

2021 ◽

Vol 13 (6) ◽

pp. 999

Author(s):

Sue E. Crawford ◽

Sasirekha Ramani ◽

Sarah E. Blutt ◽

Mary K. Estes

Keyword(s):

Cell Types ◽

Human Infection ◽

Viral Pathogens ◽

Host Interactions ◽

Complex Interactions ◽

Microbe Interactions ◽

Host Microbe Interactions ◽

Human Intestinal Epithelium ◽

Human Viruses ◽

Human Infections

Historically, knowledge of human host–enteric pathogen interactions has been elucidated from studies using cancer cells, animal models, clinical data, and occasionally, controlled human infection models. Although much has been learned from these studies, an understanding of the complex interactions between human viruses and the human intestinal epithelium was initially limited by the lack of nontransformed culture systems, which recapitulate the relevant heterogenous cell types that comprise the intestinal villus epithelium. New investigations using multicellular, physiologically active, organotypic cultures produced from intestinal stem cells isolated from biopsies or surgical specimens provide an exciting new avenue for understanding human specific pathogens and revealing previously unknown host–microbe interactions that affect replication and outcomes of human infections. Here, we summarize recent biologic discoveries using human intestinal organoids and human enteric viral pathogens.

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How Human Mobility Models Can Help to Deal with COVID-19

Electronics ◽

10.3390/electronics10010033 ◽

2020 ◽

Vol 10 (1) ◽

pp. 33

Author(s):

Enrique Hernández-Orallo ◽

Antonio Armero-Martínez

Keyword(s):

Human Mobility ◽

Opportunistic Networks ◽

Mobility Models ◽

Key Factors ◽

Mobile Computer ◽

Heat Map ◽

Health Authorities ◽

Spatial Risk ◽

Management Plans ◽

Human Infections

One of the key factors for the spreading of human infections, such as the COVID-19, is human mobility. There is a huge background of human mobility models developed with the aim of evaluating the performance of mobile computer networks, such as cellular networks, opportunistic networks, etc. In this paper, we propose the use of these models for evaluating the temporal and spatial risk of transmission of the COVID-19 disease. First, we study both pure synthetic model and simulated models based on pedestrian simulators, generated for real urban scenarios such as a square and a subway station. In order to evaluate the risk, two different risks of exposure are defined. The results show that we can obtain not only the temporal risk but also a heat map with the exposure risk in the evaluated scenario. This is particularly interesting for public spaces, where health authorities could make effective risk management plans to reduce the risk of transmission.

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Innate and Adaptive Immune Genes Associated with MERS-CoV Infection in Dromedaries

Cells ◽

10.3390/cells10061291 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1291

Author(s):

Sara Lado ◽

Jean P. Elbers ◽

Martin Plasil ◽

Tom Loney ◽

Pia Weidinger ◽

...

Keyword(s):

Immune Response ◽

United Arab Emirates ◽

Innate Immune ◽

Disease Dynamics ◽

Genetic Pathways ◽

Immune Genes ◽

Adaptive Immune ◽

Potential Association ◽

Host Genetic ◽

Human Infections

The recent SARS-CoV-2 pandemic has refocused attention to the betacoronaviruses, only eight years after the emergence of another zoonotic betacoronavirus, the Middle East respiratory syndrome coronavirus (MERS-CoV). While the wild source of SARS-CoV-2 may be disputed, for MERS-CoV, dromedaries are considered as source of zoonotic human infections. Testing 100 immune-response genes in 121 dromedaries from United Arab Emirates (UAE) for potential association with present MERS-CoV infection, we identified candidate genes with important functions in the adaptive, MHC-class I (HLA-A-24-like) and II (HLA-DPB1-like), and innate immune response (PTPN4, MAGOHB), and in cilia coating the respiratory tract (DNAH7). Some of these genes previously have been associated with viral replication in SARS-CoV-1/-2 in humans, others have an important role in the movement of bronchial cilia. These results suggest similar host genetic pathways associated with these betacoronaviruses, although further work is required to better understand the MERS-CoV disease dynamics in both dromedaries and humans.

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